The present invention relates to a display device, and in particular to a technique useful for application to a display device employing a time-division-multiplexed driving. TFT (Thin Film Transistor) type liquid crystal modules are widely used as displays for portable equipment such as notebook personal computers or the like. Especially, liquid crystal display modules provided with a small-sized liquid crystal display panel are used as displays for portable equipment always carried such as mobile phones, for example.
Usually there are as many outputs of a drain driver (also called a video line drive circuit) for driving a liquid crystal display panel as there are video lines (also called drain lines) of the liquid crystal display panel, and each of the outputs of the drain driver is coupled to a corresponding one of the video lines.
On the other hand, for the purpose of miniaturizing a drain driver, Japanese Patent Application Laid-Open No. Hei 11-327518 Publication (which corresponds to U.S. Pat. No. 6,424,328 B1) discloses a so-called time-division-multiplexed driving method as a driving method of a liquid crystal display panel which is capable of reducing the number of output pins (output terminals) of a drain driver. In this time-division-multiplexed driving method, video lines are divided into plural units (blocks) each composed of plural video lines. Signals to be supplied to plural video lines of each of the blocks are output from the drain driver in a time-sequential fashion. The liquid crystal display panel is provided with plural time-division switches each corresponding to one of the blocks of the plural video lines, and each of the time-division switches receives the time-sequential signals outputted from the drain driver and supplies the time-sequential signals to the plural video lines of a corresponding one of the blocks in a time-sequential fashion.